On April 5, 2025, the Aysén region in Chile will remain on permanent Daylight Saving Time (DST), UTC-03, joining the Magallanes region. Please note that only the Aysén region is affected by this change, while other regions of Chile remain unaffected. This change will diverge from the America/Santiago time zone and create a new zone, America/Coyhaique.

 

When will this happen: 

On April 5, 2025, the Aysén Region in Chile, will stay in permanent Daylight Saving Time (DST), UTC-03. Microsoft plans to release an update to support this change in the April 2025 Windows security update.

 

How this will affect your organization: 

If your organization has users affected by these changes, their system will show incorrect time until the available fixes are installed. Please plan to install the April 2025 Windows security update promptly.  

 

What you need to do to prepare: 

As a workaround, until you install the April 2025 Windows security update, we recommend that users set the time zone on their devices to “(UTC-3) Punta Arenas” on April 5, 2025, at 12:00 A.M. (midnight). Selecting this time zone will ensure that devices reflect the correct local time, i.e., Magallanes Standard time. (Note: Events that have occurred in the past, before the update, will not show correctly.)

This can be done in one of the two ways: 

 

Additional information: